The present invention relates to an axle lift to be mounted to a wheel axle suspension of a utility vehicle such as a truck, a trailer or a semi-trailer. These kind of vehicles often have multiple wheel axles, each suspended by an air sprung wheel axle suspension. In some circumstances not all axles have to be used, for example when the vehicle is not fully loaded. The purpose of the axle lift mounted to one of the axle suspensions is to lift the wheel axle such that the wheels are lifted from the road surface. Thereby the rolling resistance of the vehicle is reduced, which saves fuel, and the wear of the tyres over time is reduced.

Axle lifts are known. For example Fig. 2 of EP 0 450 942 shows an axle lift comprising a lever which has a front arm and a rear arm. Between the front arm and rear arm the lever is pivotally suspended from a bearing bracket. An actuator is located in front of the bearing bracket and is attached to the front end of the front arm of the lever. The opposite side of the actuator is supported by a support mounted to the chassis. The rear end of the rear arm of the lever arm is provided with a rubber pad which engages an underside of the trailing arm at a distance rearward of the pivot around which the trailing arm rotates.

Another type of axle lift includes a support that is attached or suspended from the bearing bracket and is generally located underneath the bearing bracket. An actuator is attached with one end (a lower end) to the support. The opposite end of the actuator is attached or engages the trailing arm at a distance from the pivot of the trailing arm. Examples of this type of axle lift are shown in EP 431 673, EP 941 915, US 5655788, WO 98/38074 and EP 3489 047.

It is an object of the invention to provide an alternative axle lift construction.

This object is achieved by an axle lift for an air sprung wheel axle suspension of a utility vehicle such as a truck, a trailer or a semi-trailer, said axle lift comprising a lever and an actuator having opposite ends. One of said opposite ends of the actuator is supported by a support structure, and the other one of said opposite ends of the actuator is attached to an actuator mounting portion on the lever. Remote from the actuator mounting portion, the lever has a trailing arm mounting portion adapted to be rigidly attached to a pivoting end structure of a trailing arm of the wheel axle suspension so as to transfer a rotational moment in the pivoting end structure of the trailing arm, which drives a lifting movement of the trailing arm. The axle lift according to the invention comprises a rigid lever adapted to be rigidly attached to a pivoting end structure of a trailing arm of the wheel axle suspension. This attachment is rigid, such that a rotation of the lever at the attachment causes a rotation of the pivoting end structure, e.g. an eyelet, of the trailing arm. The rigid attachment may be based on clamping and friction (“Kraftschlussig), but may also be based interlocking (“Formschlussig”). The lever is furthermore attached to the other end of said opposite ends of the actuator, at a location remote from the location where the lever is attached to said pivoting end structure. The lever thus constitutes a moment-arm, wherein the pivot of the lever is the pivot of the trailing arm. Extension or expansion of the actuator causes a swivelling movement of the lever around the pivot of the lever. Since the lever is attached to the trailing arm at the pivoting end structure of the trailing arm, the trailing arm mounting portion transfers the moment in the pivoting end structure of the trailing arm and the trailing arm is forced to rotate around its pivot, whereby the remainder of the trailing arm is swivelled upwardly, and consequently the axle is lifted. Thus, in other words, when the actuator applies a force on the actuating mounting portion of the lever and the force of the actuator is converted into a rotational moment by the lever, the trailing arm mounting portion of the lever, due to the rigid connection with the pivoting end structure of the trailing arm, transfers said rotational moment to said pivoting end structure, whereby the trailing arm is swivelled upwardly. The actuator thus drives an upward swivelling movement of the trailing arm by driving a rotation directly at the pivoting end structure of the trailing arm. The pivoting end structure of the trailing arm may for example be an eyelet, which is common on trailing arms.

It is emphasized that according to the invention the lever only interacts with the trailing arm at the pivoting end structure of the trailing arm. There is thus explicitly no engagement of the lever or the actuator with the trailing arm, e.g. with an intermediate cushion element, at another location on the trailing arm remote from the pivoting end structure, which is for example the case in EP 431 673, EP 941 915, WO 98/38074 and EP 3489 047. These prior art axle lift constructions comprise a positioning arm or guiding arm attached to the upper end of the actuator, which positioning arm or guiding arm is not rigidly attached to the eyelet of the trailing arm and can move with respect to the eyelet. At the end of the positioning arm where the actuator is attached to it, the positioning arm is provided with a cushioning element which engages the underside of the trailing arm, to push the trailing arm upwardly upon extension of the actuator.

In case of a flexible trailing arm, according to the invention there is thus no component of the axle lift engaging on the spring portion of the trailing arm. Because there are no other engagement points between the lever/actuator and the trailing arm than at the pivoting end structure, there are no mutually shifting components, which prevents friction and wear of the components. Moreover, the load on the pivot of the trailing arm is also reduced by this and can be lighter. Furthermore, protective elements, such as rubber pads or other cushioning elements are not necessary, which saves components and weight.

In an embodiment the trailing arm mounting portion of the lever is adapted to be clamped to the pivoting end structure of the trailing arm.

In a further embodiment the trailing arm mounting portion of the lever comprises a seat portion to receive a part of the pivoting end structure of the trailing arm and wherein the axle lift furthermore comprises at least one clamping means to tighten the pivoting end structure of the trailing arm in the seat portion.

The clamping means may comprise one or more threaded bolts. The clamping means may comprise a ll-bolt having threaded legs.

In an embodiment the trailing arm mounting portion of the lever is adapted to be hooked to the pivoting end structure of the trailing arm.

In such an embodiment the trailing arm mounting portion of the lever may comprise a portion that extends underneath the pivoting end structure of the trailing arm, wherein said portion has an end which is connectable to a rear end, i.e. a trailing arm sided end, of the pivoting end structure by a fastener, e.g. a bolt, and the trailing arm mounting portion of the lever may comprise a hook adapted and arranged to engage over a front end edge portion of the pivoting end structure of the trailing arm.

In a further embodiment said portion that extends underneath the pivoting end structure of the trailing arm is connectable to the front end of the pivoting end structure by a fastener, e.g. a bolt.

In a possible embodiment the axle lift is adapted to be retrofitted.

In an embodiment the axle lift furthermore comprises a support console which is adapted to be mounted to a bearing bracket of the wheel axle suspension, wherein the support console forms said support structure. In another embodiment the axle lift furthermore comprises a support console which is adapted to be mounted to a vehicle chassis, wherein the support console forms said support structure.

The invention also relates to a wheel axle suspension for a utility vehicle such as a truck, a trailer or a semi-trailer, wherein the wheel axle suspension comprises a bearing bracket attached to a vehicle chassis, a trailing arm having a pivoting end structure, which is pivotally mounted to the bearing bracket, an axle body mounted to the trailing arm, an air spring mounted to the trailing arm and supporting the chassis. The wheel axle suspension furthermore includes an axle lift as described in the above.

The invention also relates to a wheel axle suspension for a utility vehicle such as a truck, a trailer or a semi-trailer, wherein the wheel axle suspension comprises a bearing bracket attached to a vehicle chassis; a trailing arm having a pivoting end structure, which is pivotally mounted to the bearing bracket; an axle body mounted to the trailing arm; and an air spring mounted to the trailing arm and supporting the chassis. The wheel axle suspension furthermore includes an axle lift to lift the wheel axle, the axle lift comprising a lever and an actuator having opposite ends. One of said opposite ends of the actuator is supported by a support structure, and the other one of said opposite ends of the actuator is attached to an actuator mounting portion of the lever. Remote from the actuator mounting portion, the lever has a trailing arm mounting portion which is rigidly attached to the pivoting end structure of the trailing arm so as to transfer a rotational moment in the pivoting end structure of the trailing arm, which drives a lifting movement of the trailing arm.

A wheel axle suspension according to the invention includes an axle lift which comprises a rigid lever that is rigidly attached to a pivoting end structure of a trailing arm of the wheel axle suspension. The attachment of the lever to the pivoting end structure is rigid, such that a rotation of the lever at the attachment causes a rotation of the pivoting end structure, e.g. an eyelet, of the trailing arm. The rigid attachment may be based on clamping and friction (“Kraftschlussig), but may also be based interlocking (“Formschlussig”). The lever is furthermore attached to the other end of said opposite ends of the actuator, at a location remote from the location where the lever is attached to said pivoting end structure. The lever thus constitutes a moment-arm, wherein the pivot of the lever is the pivot of the trailing arm. Extension or expansion of the actuator causes a swivelling movement of the lever around the pivot of the lever. Since the lever is rigidly attached to the trailing arm at the pivoting end structure of the trailing arm, the trailing arm mounting portion transfers the moment to the pivoting end structure of the trailing arm and the trailing arm is forced to rotate around its pivot, whereby the remainder of the trailing arm is swivelled upwardly, and consequently the axle is lifted. Thus, in other words, when the actuator applies a force on the actuating mounting portion of the lever and the force of the actuator is converted into a rotational moment by the lever, the trailing arm mounting portion of the lever, due to the rigid connection with the pivoting end structure of the trailing arm, transfers said rotational moment to said pivoting end structure, whereby the trailing arm is swivelled upwardly. The actuator thus drives an upward swivelling movement of the trailing arm by driving a rotation directly at the pivoting end structure of the trailing arm.

In an embodiment of the wheel axle suspension the pivoting end structure of the trailing arm comprises an eyelet, which eyelet may be integrally formed on the trailing arm. For example the trailing arm may be formed by a rolling or forging process, and the front end of the trailing arm is bent to an eyelet which is in one piece with the remainder of the trailing arm.

In another embodiment the pivoting end structure of the trailing arm comprises an integral eyelet portion that is integrally formed on the trailing arm, wherein a separate eyelet portion is attached to said integral eyelet portion to form an eyelet. The separate eyelet portion may be bolted to the integral eyelet portion, preferably by means of a ll-bolt or one or more bolts.

In a particular embodiment of the suspension, the trailing arm mounting portion of the lever comprises the separate eyelet portion. In this specific embodiment the trailing arm mounting portion thus integrates two functions: It connects the lever to the trailing arm at the pivoting structure of the latter, and it forms a portion of the eyelet, complementary with the eyelet portion that is formed in one piece with the trailing arm. An advantage of this embodiment is a less material use and thus weight saving. This embodiment of the axle lift is less suitable to be retrofitted.

Preferably the trailing arm mounting portion of the lever is bolted to the integral eyelet portion with the same ll-bolt, or the same one or more bolts as the separate eyelet portion is bolted to the integral eyelet portion with. Between the eyelet portions a bearing element comprising a rubber bushing can be clamped, a so called “silent block”, which provides the pivot for the trailing arm with respect to the bearing bracket.

In an embodiment of the wheel axle suspension the support structure comprises a support console which is mounted to the bearing bracket, wherein the actuator is located underneath the bearing bracket. This support console is as such of a known type. However, in this embodiment the lever which is attached to the top end of the actuator extends from said top end of the actuator to the front towards the pivoting structure, often an eyelet, of the trailing arm.

In another embodiment the support structure comprises a support console which is mounted to the vehicle chassis in front of the bearing bracket, wherein the actuator is located in front of the bearing bracket. In this embodiment the lever which is attached to the bottom end of the actuator extends from said bottom end of the actuator to the rear towards the pivoting structure, often an eyelet, of the trailing arm.

In another embodiment the support structure comprises a chassis beam of the vehicle chassis, wherein the actuator is located in front of the bearing bracket. In this embodiment the top end of the actuator is directly attached to the chassis beam, e.g. a lower flange of a chassis beam. The lever is attached to the bottom end of the actuator extends from said bottom end of the actuator to the rear towards the pivoting structure, often an eyelet, of the trailing arm.

In a particular embodiment, the trailing arm mounting portion of the lever comprises a seat portion in which, at least partially, the integral eyelet portion of the trailing arm is received. The lever of this embodiment may have a blind bore (non-threaded) on one side, preferably the rear side, of the seat portion, in which blind bore one end of a leg of the ll-bolt is received. Furthermore the lever may have a through bore on another side, preferably the front side, of the seat portion, through which bore an end of another leg of the ll-bolt is passed, wherein a second nut is screwed on said end to fix the lever to said leg.

In another embodiment of the wheel axle suspension the pivoting end structure of the trailing arm comprises a hammerhead comprising two opposite journalling portions, which are each received in a corresponding journalling recess in a side plate of the bearing bracket, and which define a pivot axis of the pivoting end structure. The hammerhead is preferably formed in one piece with the remainder of the trailing arm although also embodiments can be envisaged in which the hammerhead or components thereof are formed separately and connected to the remainder of the trailing arm.

In a further embodiment the pivoting end structure has between the journaling portions of the hammerhead an attachment portion adapted to cooperate with the trailing arm mounting portion of the lever. In a further embodiment said attachment portion of the pivoting end structure has a bore extending substantially perpendicular to the pivot axis, and wherein the trailing arm mounting portion of the lever has a bore which is aligned with said bore in the attachment portion of the pivoting end structure, and wherein a fastener, e.g. a bolt, extends through said aligned bores to attach said attachment portion and said trailing arm mounting portion to each other.

In a further embodiment the support structure comprises a support console which is mounted to the bearing bracket and wherein the actuator is located underneath the bearing bracket.

The invention will be further elucidated in the following description with reference to the drawings, in which:

Fig. 1 shows a side elevational view of a wheel axle suspension including a first embodiment of an axle lift according to the invention,

Fig. 2 shows a isometrical view of the wheel axle suspension of Fig. 1,

Figs. 3a - 3e show the axle lift shown in the suspension of Fig. 1 in a side view, a top view, a front view, a rear view and a bottom view, respectively,

Figs 4a and 4b show the axle lift of Fig. 3a - 3e in different isometric views,

Fig. 5 shows an isometric view of an assembly of a trailing arm, an axle body and an axle lift of the wheel axle suspension of Fig. 1 ,

Fig. 6 shows a cross section in a longitudinal direction of a front part of the assembly of Fig. 5,

Figs. 7a - 7e show a lever of the axle lift of Fig. 3 in a side view, a top view, a front view, a rear view and a bottom view, respectively,

Figs 8a and 8b show the lever of Figs 7a - 7e in in different isometric views,

Fig. 9 shows a side elevational view of a wheel axle suspension including a second embodiment of an axle lift according to the invention,

Fig. 10 shows a isometrical view of the wheel axle suspension of Fig. 9, Fig. 11 shows a cross section in a longitudinal direction of a front part of the assembly of a trailing arm and the axle lift shown in Figs 9 and 10,

Figs. 12a and 12b show a lever of the second embodiment of the axle lift in different isometric views,

Fig. 13 shows a side elevational view of a wheel axle suspension including a third embodiment of an axle lift according to the invention,

Fig. 14 shows a isometrical view of the wheel axle suspension of Fig. 13,

Fig. 15 shows a cross section in a longitudinal direction of a front part of the assembly of a trailing arm and the axle lift shown in Figs 13 and 14,

Figs. 16a and 16b show a lever of the third embodiment of the axle lift in different isometric views,

Fig. 17 shows a side elevational view of a wheel axle suspension including a fourth embodiment of an axle lift according to the invention,

Fig. 18 shows an isometrical view of the wheel axle suspension of Fig. 17,

Fig. 19 shows a cross section in a longitudinal direction of a front part of the assembly of a trailing arm and the axle lift shown in Figs 17 and 18,

Figs. 20a and 20b show a lever of the fourth embodiment of the axle lift in different isometric views,

Fig. 21 shows a side elevational view of a wheel axle suspension including a fifth embodiment of an axle lift according to the invention,

Fig. 22 shows an isometrical view of the wheel axle suspension of Fig. 21,

Figs. 23a and 23b show a lever of the fifth embodiment of the axle lift in an isometric view and a side elevational view, respectively, Fig. 24 shows an isometrical view of a part of a wheel axle suspension including a sixth embodiment of an axle lift according to the invention,

Fig. 25 shows an isometrical view of the trailing arm and a part of the axle lift of the wheel axle suspension of Fig. 24,

Fig. 26 shows a sectional view of the front end of the wheel axle suspension of Fig. 24,

Fig. 27 shows an isometrical view of a trailing arm of the wheel axle suspension of Fig. 24, and

Figs. 28a and 28b show a lever of the sixth embodiment of the axle lift in an isometric view and a side elevational view, respectively.

In Figs 1 and 2 is shown an air sprung wheel axle suspension 1 which can be arranged on a utility vehicle such as a truck, a trailer or a semi-trailer. The wheel axle suspension 1 comprises a bearing bracket 2 which attached to a vehicle chassis 3. The bearing bracket comprises two spaced apart side plates 21. The vehicle chassis 3 is indicated by a chassis beam 31 drawn in dashed lines. The bearing bracket 2 has an upper end that is attached to a flange of the chassis beam 31, it may for example be welded to the chassis beam 31.

The suspension 1 furthermore comprises a trailing arm 4. The trailing arm 4 has a pivoting end structure 45, which is arranged between the side plates 21 of the bearing bracket 2 and is pivotally mounted thereto by means of a pivot bolt 5 that extends through aligned openings in the side plates 21.

The pivoting end structure 45 of the trailing arm 4 comprises in this specific embodiment an integral eyelet portion 47 that is integrally formed on the trailing arm 4, for example by means of a forging process. A separate eyelet portion 48 is attached to said integral eyelet portion 47 to form an eyelet. The separate eyelet portion 48 is made separately from the trailing arm, e.g by forging, or for example casting. The separate eyelet portion 47 is bolted to the integral eyelet portion 48 by means of a ll-bolt 102. Instead of a ll-bolt 102 the eyelet portions 47 and 48 could also be bolted together by one or more bolts. An axle body 6 is mounted to the trailing arm 4. The axle body 6 is in this example a thinwalled tubular axle body having a circular cross section. It is noted that other axle bodies having a different cross section are possible within the context of the present invention.

In this specific embodiment of the suspension, the trailing arm 4 comprises a front arm part 41 and a rear arm part 43, which each comprise an axle seat 42 and 44 respectively. The axle body 6 is received in the axle seats 42 and 44, and the axle seats 42 and 44 are tightened towards each other and thereby clamped to the axle body 6 by means of a bolted connection, in this specific embodiment by U-bolts 7. The trailing arm 4 is thus rigidly attached to the axle body 6.

The rear arm part 43 has an air spring mounting portion 46 at a rear end. An air spring 8 is mounted to the air spring mounting portion 46 of the trailing arm 4. The chassis 3 is supported from below by the air spring 8. An upper end 81 of the air spring 8 may for example be attached to the chassis beam 31.

The wheel axle suspension 1 furthermore includes an axle lift 9 to lift the wheel axle. The axle lift 9 comprises a lever 91 and an actuator 95 having opposite ends 96 and 97, as can be best seen in Figs 5 and 6. In this embodiment the axle lift 9 comprises a support console 98 which is suspended from the bearing bracket 2. In particular the support console has arms 98A which are suspended to the side plates 21 by means of bolts 100 and nuts 101, which are best visible in Figs 3 and 4. The support console 98 has a mounting surface 99 to which a lower end 96 of the actuator 95 is attached. The actuator 95 is located below the bearing bracket 2, as is best seen in Figs 1 and 2. The other end 97 of the actuator 9 is attached to an actuator mounting portion 92 of the lever 91.

The lever 91 has a trailing arm mounting portion 93, which is rigidly attached to a pivoting end structure 45 of the trailing arm 4. In particular, in this embodiment the trailing arm mounting portion 93 of the lever 91 is bolted to the integral eyelet portion 47 with the same ll-bolt 102 as the separate eyelet portion 48 is bolted to the integral eyelet 47 portion with. This is best visible in Fig. 6. The bent portion of the ll-bolt 102 extends around the separate eyelet portion 48. The legs of the ll-bolt 102 extend through through-bores in the integral eyelet portion. Nuts 103 and 104 are screwed on the legs of the ll-bolt 102 and fix the integral eyelet portion 47 and the separate eyelet portion 48 to each other.

As can be best seen in Figs 7a - 7e and Figs 8a and 8b, the trailing arm mounting portion 93 of the lever 91 comprises a seat portion 93A in which, at least partially, the integral eyelet portion 47 of the trailing arm 4 is received (cf. Fig. 6). The trailing arm mounting portion 93 of the lever 91 has a blind bore 93B on one side, in this case the rear side, of the seat portion 93A, which is best seen in Fig. 8a. In the blind bore 93B one end of a leg of the ll-bolt 102 is received as is best seen in Fig. 6. The nut 104 which is screwed on this leg of the ll-bolt rests on a surface of the trailing arm mounting portion 93 surrounding the blind bore 93B (cf. Fig. 6). On the other side of the seat portion 93A, in this embodiment the front side, the lever 91 has a through bore 93C which is best seen in Figs 8a and 8b. In this bore 93C the end of the other leg of the ll-bolt 102 is inserted with the nut 103, which is best seen in Fig. 6. The nut 103 is thus received in the bore 93C. A second nut 105 is screwed on the end of the same leg of the ll-bolt to rigidly fix the lever 93 to said leg. This embodiment of the lever 91 and thus the axle lift 9 is suitable to be retrofitted to this wheel axle suspension, because the nuts 103 and 104 for fixing the eyelet portions together do not have to be released to mount the lever to the eyelet.

The actuator mounting portion 92 of the lever 91 and the trailing arm mounting portion 93 of the lever 91 are remote from each other. The pivot of the lever 91 is the pivot of the trailing arm 4. Extension or expansion of the actuator 95 causes a swivelling movement of the lever 91 around the pivot of the lever 91. Since the lever 91 is rigidly attached to the trailing arm 4 at the pivot structure 45 of the trailing arm 4, the rotation of the lever 91 drives the rotation of the trailing arm 4 at the pivot. Thus the trailing arm 4 swivels around its pivot, whereby the remainder 41, 43 of the trailing arm 4 is lifted, and consequently the axle 6 is lifted.

In Figs 9 and 10 another embodiment of an air sprung wheel axle suspension according to the invention is shown. The wheel axle suspension is indicated by reference numeral 201 and can be arranged on a utility vehicle such as a truck, a trailer or a semi-trailer. The wheel axle suspension 201 comprises a bearing bracket 202 which is attached to a vehicle chassis 203. The bearing bracket 202 comprises two spaced apart side plates 221. The vehicle chassis 203 is indicated by a chassis beam 231 drawn in dashed lines. The bearing bracket 202 has an upper end that is attached to a flange of the chassis beam 231 , it may for example be welded to the chassis beam 231.

The suspension 201 furthermore comprises a trailing arm 204. The trailing arm 204 has a pivoting end structure 245, which is arranged between the side plates 221 of the bearing bracket 202 and is pivotally mounted thereto by means of a pivot bolt 205 that extends through aligned openings in the side plates 221. The pivoting end structure 245 of the trailing arm 204 comprises in this specific embodiment an integral eyelet portion 247 that is integrally formed on the trailing arm 204, for example by means of a forging process. A separate eyelet portion 248 is attached to said integral eyelet portion 247 to form an eyelet. The separate eyelet portion 248 is made separately from the trailing arm, e.g. by forging, or for example casting. The separate eyelet portion 247 is bolted to the integral eyelet portion 248 by means of a ll-bolt 302 as is best seen in Fig 11. Instead of a ll-bolt 302 the eyelet portions 247 and 248 could also be bolted together by one or more bolts.

An axle body 206 is mounted to the trailing arm 204. The axle body 206 is in this example a thin walled tubular axle body having a circular cross section. It is noted that other axle bodies having a different cross section are possible within the context of the present invention.

In this specific embodiment of the suspension, the trailing arm 204 comprises a front arm part 241 and a rear arm part 243, which each comprise an axle seat 242 and 244 respectively.

The axle body 206 is received in the axle seats 242 and 244, and the axle seats 242 and 244 are tightened towards each other and thereby clamped to the axle body 206 by means of a bolted connection, in this specific embodiment by U-bolts 207. The trailing arm 204 is thus rigidly attached to the axle body 206.

The rear arm part 243 has an air spring mounting portion 246 at a rear end. An air spring 208 is mounted to the air spring mounting portion 246 of the trailing arm 204. The chassis 203 is supported from below by the air spring 208. An upper end 281 of the air spring 208 may for example be attached to the chassis beam 231.

The wheel axle suspension 201 furthermore includes an axle lift 209 to lift the wheel axle. The axle lift 209 comprises a lever 291 and an actuator 295 having opposite ends 296 and 297, as can be best seen in Figs 9 and 11. In this embodiment the axle lift 209 comprises a support console 298 which attached to the overhead chassis beam 231. The support console 298 has a mounting surface 299 to which an upper end 297 of the actuator 295 is attached. The actuator 295 is located in front of the bearing bracket 202 as is visible in Figs 9 and 10. The other end 296 of the actuator 209 is attached to an actuator mounting portion 292 of the lever 291 , which is located below the actuator 295.

The lever 291 has a trailing arm mounting portion 293 which is rigidly attached to a pivoting end structure 245 of the trailing arm 204. The trailing arm mounting portion 293 of the lever 291 is bolted to the integral eyelet portion 247 with the same ll-bolt 302 as the separate eyelet portion 248 is bolted to the integral eyelet 247 portion with. This is best visible in Fig.

11.

As can be best seen in Figs 12a and 12b, the trailing arm mounting portion 293 of the lever 291 comprises a seat portion 293A in which, at least partially, the integral eyelet portion 247 of the trailing arm 204 is received (cf. Fig. 11). The seat portion 293 engages an underside of the integral eyelet portion 247. The trailing arm mounting portion 293 of the lever 291 has a through bore 293B, 293C on either side of the seat portion 293A, which is best seen in Figs 12a and 12b. The bores 293B and 293C are aligned with bores in the integral eyelet portion 247. Through each of these bores 293B, 293C and the aligned bores in the integral eyelet portion 247 an end of a leg of the ll-bolt 302 is passed, which is best seen in Fig. 11. Nuts 303, 304 are screwed on these ends, respectively to fix the lever 293 to the legs of the ll-bolt 302. The separate eyelet portion 248, the integral eyelet portion 247 of the trailing arm 204 and the seat portion 293 of the lever 291 are thus rigidly clamped together.

The actuator mounting portion 292 of the lever 291 and the trailing arm mounting portion 293 of the lever 291 are remote from each other. The pivot of the lever 291 is the pivot of the trailing arm 204. Extension or expansion of the actuator 295 causes a swivelling movement of the lever 291 around the pivot of the lever 291. Since the lever 291 is rigidly attached to the trailing arm 204 at the pivot structure 245 of the trailing arm 204, the rotation of the lever 291 drives the rotation of the trailing arm 204 at the pivot. Thus the trailing arm 204 swivels around its pivot, whereby the remainder 241, 243 of the trailing arm 204 is lifted, and consequently the axle 206 is lifted.

In Figs 13 and 14 yet another embodiment of an air sprung wheel axle suspension according to the invention is shown. This embodiment is similar to the embodiment shown in Figs 9 and 10. The wheel axle suspension of Figs 13 and 14 has the same bearing bracket, the same trailing arm and the same air spring as the embodiment of Figs 9 and 10. Therefore the same parts are provided with the same reference numerals as in Figs 9 and 10, and for a description is referred to the above.

The wheel axle suspension 401 shown in Figs 13 and 14 has an axle lift 409 to lift the wheel axle, which is a slightly different embodiment from the axle lift embodiment shown in Figs 9 - 12b. In particular the lever and the ll-bolt with which the lever is mounted to the pivoting end structure of the trailing arm is a bit different. The integral eyelet portion 247 of the trailing arm and the separate eyelet portion 248 are connected to each other by the ll-bolt 502 that extends with its bend portion over the separate eyelet portion 248. The legs of the ll-bolt 502 extend through bores in the integral eyelet portion (cf. Fig. 15). Nuts 503, 504 are screwed on the legs to tighten the eyelet portions 247 and 248 together.

The axle lift 409 comprises a lever 491 and an actuator 495 having opposite ends 496 and 497, as can be best seen in Figs 13 and 14. In this embodiment the axle lift 409 comprises a support console 498 which attached to the overhead chassis beam 231. The support console 498 has a mounting surface 499 to which an upper end 497 of the actuator 495 is attached. The actuator 495 is located in front of the bearing bracket 202 as is visible in Figs 13 and 14. The other end 496 of the actuator 409 is attached to an actuator mounting portion 492 of the lever 491, which is located below the actuator 495.

The lever 491 has a trailing arm mounting portion 493 which is rigidly attached to a pivoting end structure 245 of the trailing arm 204. The trailing arm mounting portion 493 of the lever 491 is bolted to the integral eyelet portion 247 with the same ll-bolt 502 as the separate eyelet portion 248 is bolted to the integral eyelet 247 portion with. This is best visible in Fig. 15.

As can be best seen in Figs 16a and 16b, the trailing arm mounting portion 493 of the lever 491 comprises a flat engagement portion 493A which engages the integral eyelet portion 247 of the trailing arm 204 is received (cf. Fig. 15). The trailing arm mounting portion 493 of the lever 491 has a through bore 493B, 493C on either side of the engagement portion 493A, which is best seen in Figs 16a and 16b. In each of these bores 493B, 493C an end of a leg of the ll-bolt 502 is inserted, which is best seen in Fig. 15. The respective nuts 503 and 504, screwed on these ends, engage the surface surrounding the bores 493B and 493C. In the bore 493B an additional nut 505 is inserted from below and screwed on the corresponding leg of the ll-bolt 502, as is visible in Fig. 15. The nut 505 has a collar that engages the lower surface surrounding the bore 493B. Thus the nut 505 tightens the lever 491 into engagement with the nuts 503 and 504 and with the integral eyelet portion 247 of the trailing arm 204. This embodiment of the lever 491 and thus the axle lift 409 is suitable to be retrofitted to this wheel axle suspension, because the nuts 503 and 504 for fixing the eyelet portions 247 and 248 together do not have to be released to mount the lever 491 to the eyelet.

The actuator mounting portion 492 of the lever 491 and the trailing arm mounting portion 493 of the lever 491 are remote from each other. The pivot of the lever 491 is the pivot of the trailing arm 204. Extension or expansion of the actuator 495 causes a swivelling movement of the lever 491 around the pivot of the lever 491. Since the lever 491 is attached to the trailing arm 204 at the pivot structure 245 of the trailing arm 204, the trailing arm 204 also swivels around its pivot, whereby the remainder 241, 243 of the trailing arm 204 is lifted, and consequently the axle 206 is lifted.

In Figs 17 and 18 yet another embodiment of an air sprung wheel axle suspension according to the invention is shown. This embodiment is similar to the embodiment shown in Figs 9 and 10. The wheel axle suspension of Figs 17 and 18 has the same bearing bracket, the same trailing arm and the same air spring as the embodiment of Figs 9 and 10. Therefore the same parts are provided with the same reference numerals as in Figs 9 and 10, and for a description is referred to the above.

The wheel axle suspension 601 shown in Figs 17 and 18 has an axle lift 609 to lift the wheel axle, which is a different embodiment from the axle lift embodiments shown in Figs 9 - 16b. In particular the lever and the ll-bolt with which the lever is mounted to the pivoting end structure of the trailing arm is different.

The integral eyelet portion 247 of the trailing arm 204 is the same as in the previous embodiments.

The axle lift 609 comprises a lever 691 and an actuator 695 having opposite ends 696 and 697, as can be best seen in Figs 17 and 18. In this embodiment the axle lift 609 comprises a support console 698 which attached to the overhead chassis beam 231. The support console 698 has a mounting surface 699 to which an upper end 697 of the actuator 695 is attached. The actuator 695 is located in front of the bearing bracket 202 as is visible in Figs 17 and 18. The other end 696 of the actuator 609 is attached to an actuator mounting portion 692 of the lever 691, which is located below the actuator 695.

The lever 691 has a trailing arm mounting portion 693 which is formed as a separate eyelet portion for forming an eyelet together with the integral eyelet portion 247 of the trailing arm. The eyelet is part of the pivoting end structure of the trailing arm 204. The trailing arm mounting portion 693 of the lever 691 has a bore 693B through which one leg of a ll-bolt 702 passes. The trailing arm mounting portion 693 has on an upper side a groove 693D which extends from an upper end of the bore 693B to a rear end of the trailing arm mounting portion 693 rearwardly. The bend portion of the ll-bolt 702 and the other leg of the ll-bolt 702 are received in the groove 693D. This is best visible in Figs 19 and 20A. This embodiment of the axle lift has less parts and may save some weight. Moreover the lever is located higher, whereby it is suitable for suspensions with a lower ride height.

In all of the embodiments described in the above the trailing arm 4, 204 has an integral eyelet portion 47, 247 and a separate eyelet portion 48, 248, 693 that together form the eyelet. Between the eyelet portions a bearing element 50 comprising a rubber bushing 51 with on an inner side a metal bushing 52 can be clamped, a so called “silent block”. The ends of metal bushing 52 are clamped against the side plates 21 , 221 of the bearing bracket 2, 202 by means of the pivot bolt 5205. This provides the pivot structure for the trailing arm 4, 204 with respect to the bearing bracket 2, 202.

It is noted that also other embodiments are possible in which the trailing arm has an entire eyelet formed at a front end. This is a common structure which can be combined with an axle lift according to the invention. The only requirement is that the lever of the axle lift can be or is rigidly attached to the trailing arm at the eyelet, such that the pivot of the lever coincides with the pivot of the trailing arm. According to the invention it is thus not necessary that the eyelet comprises two portions that are clamped together. Moreover, except bolting for rigidly coupling the lever to the pivoting structure of the trailing arm, it is for example also feasible to weld the lever to the pivoting end structure (e.g. an eyelet) of the trailing arm. Moreover it is noted that the axle lift according to the invention can also be mounted to trailing arms having another pivoting structure than an eyelet, for example a “hammerhead” shaped end portion with journaling extensions as is described in WO 2020/060393 can be provided with an axle lift according to the invention that has a lever with a trailing arm mounting portion adapted to be rigidly attached to the pivoting end structure of a trailing arm, in this example the hammerhead.

In Figs 21 and 22 yet another embodiment of an air sprung wheel axle suspension according to the invention is shown. This embodiment is similar to the embodiment shown in Figs 9 and 10. The wheel axle suspension of Figs 21 and 22 can have the same bearing bracket, the same trailing arm and the same air spring as the embodiment of Figs 9 and 10. Therefore the same parts are provided with the same reference numerals as in Figs 9 and 10, and for a description is referred to the above.

The wheel axle suspension shown in Figs 21 and 22 has an axle lift 709 to lift the wheel axle, which is a slightly different embodiment from the axle lift embodiment shown in Figs 9 - 10. In particular the lever is a bit different. The axle lift 709 comprises a lever 791 and an actuator 795 having opposite ends 796 and 797, as can be best seen in Fig. 21. In this embodiment the axle lift 709 comprises a support console 798 which attached to an overhead chassis beam (not shown). The support console 798 has a mounting surface 799 to which an upper end 797 of the actuator 795 is attached. The actuator 795 is located in front of the bearing bracket 202 (not shown in Figs 21 and 22, but cf. Figs 9 and 10). The other end 796 of the actuator 709 is attached to an actuator mounting portion 792 of the lever 791, which is located below the actuator 795.

The lever 791 has a trailing arm mounting portion 793 which is rigidly attached to a pivoting end structure 245 of the trailing arm 204. The trailing arm mounting portion 793 of the lever 791 is bolted to the integral eyelet portion 247 with the same ll-bolt 302 as the separate eyelet portion 248 is bolted to the integral eyelet 247 portion with. Thereto the arm has an upwardly facing surface 793A that engages the curve of the integral eyelet portion 247, and two bores 793B and 793C for passing through the legs of the ll-bolt 302, which extend from the surface 793A to an opposite side of the lever 791. The surface 793A is flat in the embodiment shown, but may also have a curved seat-like recess shape to receive a portion of the integral eyelet portion 247 of the trailing arm.

At a distance above the upwardly facing surface 793A the lever 791 has a hook 794 adapted and arranged to engage over a front end edge portion of the pivoting end structure 245 of the trailing arm 204. In this particular embodiment of the suspension the hook 794 can grip over a flange 247A on the front end of the integral eyelet portion 247. In other embodiments the hook 794 can grip over another protrusion on a front end of the pivoting end structure 245 of the trailing arm.

Advantageously the hook 794 absorbs forces from the front end of the trailing arm when the axle lift is activated. Thereby the leg of the ll-bolt 302, which extends through the bore 793B is spared when the axle lift is activated, which increases the lifetime of the ll-bolt 302.

In Figs 24-26 a part of a wheel axle suspension is shown, in which the pivoting end structure of the trailing arm comprises a hammerhead. In In this specific embodiment of the suspension, the trailing arm comprises a front arm part 841 and a rear arm part. The rear arm part is not shown in the figures, but the structure is similar to what is shown in Fig. 1. The front arm part comprises an axle seat 842. Likewise the rear arm part comprises an axle seat, comparable to what is shown in Fig. 1. The axle body is received in the axle seats, and the axle seats are tightened towards each other and thereby clamped to the axle body by means of a bolted connection, in this specific embodiment by U-bolts 7 (cf. Fig. 1). The trailing arm is thus rigidly attached to the axle body.

In Fig. 27 the front arm part 841 of the trailing arm is shown separately. The pivoting end structure 845 is formed as a hammerhead comprising two opposite journaling portions 846. The journaling portions 846 are each received in a corresponding journaling recess 848 in a side plate 847 of the bearing bracket. The journaling portions 846 define a pivot axis 849 of the pivoting end structure 845. The hammerhead is preferably formed in one piece with the remainder of the trailing arm. However, also embodiments can be envisaged in which the hammerhead or components thereof are formed separately and connected to the remainder trailing arm.

The wheel axle suspension furthermore includes an axle lift 809 to lift the wheel axle. The axle lift 809 comprises a lever 891 and an actuator 895 having opposite ends 896 and 897, as can be best seen in Fig. 26. The lever 891 , which is separately shown in Figs 28a and 28b has on one end an actuator mounting portion 892 and on an opposite end a trailing arm mounting portion 893. In this embodiment the axle lift 809 comprises a support console which is suspended from the bearing bracket. The console is not shown in the figures, but is similar to what is shown in Figs 1-4. A lower end 896 of the actuator 895 is attached to the console. The actuator 895 is located below the bearing bracket, as is best seen in Fig. 26. The other end 897 of the actuator 895 is attached to an actuator mounting portion 892 of the lever 891.

The trailing arm mounting portion 893 of the lever 891 is rigidly attached to the pivoting end structure 845 of the trailing arm. In particular, in this embodiment the trailing arm mounting portion 893 of the lever 891 is bolted to a zone between the journaling portions 846.

The pivoting end structure 845 has between the journaling portions 846 of the hammerhead form an attachment portion 850 adapted to cooperate with a trailing arm mounting portion of a lever of the axle lift.

The attachment portion 850 of the pivoting end structure has a bore 851 extending substantially perpendicular to the pivot axis 849. The trailing arm mounting portion 893 of the lever 891 has a bore 894 which is aligned with said bore 851 in the attachment portion of the pivoting end structure 845. A bolt 902 extends through said aligned bores 851 and 894 (cf. Fig. 26) to attach said attachment portion 850 and said trailing arm mounting portion 893 to each other. The trailing arm mounting portion 893 has a substantially flat upwardly facing surface 893A, which is in engagement with an underside surface portion 841A of the trailing arm adjoining the hammerhead as is best visible in Fig. 26. The surfaces 893A and 841A are clamped in tight engagement with each other by means of the bolt 902 and a cooperating nut.